HOUSTON, -- A newspaper war is brewing in Texas. Or make that a newspaper guerra.

Knight Ridder Inc., the nation's second-largest newspaper publisher after the Gannet Corporation, said today that it would expand publication of its Spanish-language paper in the Dallas-Fort Worth area, responding to demographic changes in North Texas and increased competition from the Belo Corporation, which owns The Dallas Morning News and has announced its own plan for a daily Spanish-language paper.
 

Knight Ridder, which owns The Fort Worth Star-Telegram, currently publishes the paper La Estrella twice a week. It will switch to publishing it five days a week starting Sept. 2 with the new name Diario La Estrella, the paper's publisher, Javier J. Aldape, said. Belo, which is based in Dallas, had said earlier this year that on Sept. 29 it would start publishing the Spanish-language daily newspaper, Al Día.
 

Both papers will be competing for readers and advertisers in a fast-changing market. Latinos account for 22 percent of the 5.9 million people in the Dallas-Fort Worth metropolitan area, according to Claritas, a demographic market research company in San Diego. Dallas and Fort Worth already have a thriving broadcast market in Spanish.
 

Estimates vary, but executives from Knight Ridder and Belo said that Spanish is the primary language for 75 to 80 percent of the 1.3 million Hispanics in the area; most recent arrivals are coming from Mexico. Spurring both companies to expand their Spanish-language operations are estimates projecting the Latino population of Dallas-Fort Worth to grow 21 percent by 2007, outstripping the growth rates in other cities with large numbers of Hispanics, including Los Angeles, Miami and New York.
 

"The demographics of the market are impossible to ignore," said Gilbert Bailon, president and editor of Al Día and a former executive editor of The Morning News. Asked if there was room for two Spanish-language papers there, Mr. Bailon said: "I think there is, and readers and advertisers will benefit from having a choice. It will certainly make us work harder."
 

Both Al Día (loosely translated as "Current" or "Of the Day") and Diario La Estrella ("Daily Star") plan to use editorial content from their parent organizations as well as from their own editorial staffs. Al Día, for instance, would be able to publish translated reports from the seven Latin American correspondents at The Morning News, in addition to articles from Belo's newspaper partners in Mexican cities like Guadalajara and Guanajuato.
 

La Estrella, for its part, will have access to editorial content produced by Knight Ridder newspapers like The Star-Telegram, The Miami Herald and El Nuevo Herald, a Spanish-language daily published in Miami. Neither Knight Ridder, which is based in San Jose, Calif., nor Belo would specify how much they were investing in the newspapers. Both companies plan to use existing relationships with advertisers by allowing customers to buy ads in Diario La Estrella and The Star-Telegram, for example, or in Al Día and The Morning News.
 

"The key is to leverage off the existing English-language product, while preserving the identity of the Spanish-language paper," said Alberto Ibargüen, publisher of The Herald, which is providing La Estrella with advice and loaning it some of its staff.
 

Diario La Estrella will circulate about 25,000 copies daily. Al Día plans to circulate about 40,000. Mr. Aldape, a native of South Texas who worked as managing editor of El Telégrafo, a newspaper in Guayaquil, Ecuador, before returning to Texas five years ago to work at La Estrella, said success would depend on understanding the market.
 

"There's that myth that Latinos don't read," Mr. Aldape said. "We're out there to shatter that myth."